Fagan had been jailed previously for taking part in the riots which shook London in the summer of 2011.

The incident on March 27 in Upper Street, one of Islington’s busiest roads, left pools of blood in the street and the victim’s hand hanging by a thread.

Cllr Paul Convery, Islington Council’s executive member for community safety said at the time: “There were huge puddles of blood in the street.

“There had been a period of relative calm in the borough over the last two years and the police took out a large number of very active gang members.

“They are nearly all gone but a vacuum seems to have been created with youngsters moving in to a very active drug culture – there has been a probable upswing in gang-related violence.

“We are going to get a grip on this, before it causes the kind of problems it did a couple of years ago.”

Fagan, of Dawlish Road, Tottenham, pleaded guilty to affray and carrying a bladed weapon in public. He was remanded in custody and will be sentenced at the same court on July 31, but was warned a jail sentence is being considered.

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